Shield for rear-end portion of cathode-ray tubes



Dec. 7, 1954 J. B. SEEVER 2,695,609

SHIELD FOR REAREND PORTION OF CATHODE-RAY TUBES Filed April 2. 1954 INVENTOR. JOHN B. SEEVER ATTORNEYS SHIELD FOR REAR-END PORTION OF CATHODE-RAY TUBES John B. Scever, Chicago, Ill., assignor to Cortland Industries, Inc., Chicago, 111., a corporation of Illinois Application April 2, 1954, Serial No. 420,650

6 Claims. (Cl. 340-367) This invention relates to shielding devices and more particularly to an arrangement which will enclose and protect the end of the cathode ray tube of a television receiving set projected beyond the Wall of the cabinet in which the tube is housed.

It has been found to be advantageous to extend one end of the cathode tube of a television receiving set through the rear wall of the cabinet in which the tube is mounted because this enables the utilization of a cabinet of restricted depth from the front to the rear thereof. Moreover, by projecting such a tube beyond the rear wall of the cabinet, it is possible to prevent the cabinet being placed tightly against an adjacent wall in such a way as might impair dissipation of heat from the cabinet. When the end of the cathode ray tube is extended in the above described manner, it is, of course, necessary to protect the same and to this end resort has been had to shields of several different kinds for enclosing the projecting end of such tube and which are secured in ditferent manners to the rear wall of the cabinet in which the tube is housed. In prior shields the arrangement has been such that in mounting the shield on the cabinet of the television receiving set it is necessary to pass the shield from the inside of the set out through the opening in the rear wall of the cabinet where the projected end of the cathode ray tube is to be disposed. It is further necessary to mount such shields on the rear wall of the cabinet prior to installing such wall on the television set cabinet, and consequently, to gain access to the end of the tube it is necessary either to destroy the shield or to remove the rear wall of the cabinet.

Accordingly, the primary object of the present invention is to construct a shielding device of the aforementioned kind in such a manner as to enable this shield to be mounted on the television receiving cabinet from the outside thereof without need for mounting the shield from the inside of the cabinet as has heretofore been necessary.

It is desirable that a shield of the aforesaid kind be retained in place to assure against undesired displacement thereof, and a further object of the present invention is to enable this to be accomplished in an expeditious and economical manner. Specifically, a further object of the invention in this connection is to form the shield with a flange and a metallic lip on the flange passable through a slot in a wall of the cabinet housing the cathode ray tube so that the lip will engage the inside of the wall as a barb preventing inadvertent dismounting of the shield.

Other and further objects of the present invention are to permit a shielding device for the projected end of a cathode ray tube in a television receiving cabinet to be fabricated from relatively inexpensive material such as cardboard or the like possessing some inherent flexibility and the requisite strength to permit such a shielding device to be fabricated from a single piece of such material; and to so construct the shield that the rear wall thereof, when mounted about the cathode ray tube, will be spaced from the end of the tube so that it cannot easily be pressed against the end of the tube such as to cause damage thereto.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawing which, by way of illustration, shows preferred embodiments of the present invention and the principles thereof and what I now consider to be the best mode in which I have contemplated applying these principles. Other embodiments of the invention embodying the same or equivalent prin- States Patent 2,696,609 Patented Dec. 7, 1954 a shielding device constructed along the lines of the present invention;

Fig. 2. is an elevation of the wall W of the cabinet shown in Fig. 1 with the shielding device removed therefrom;

Fig. 3 is a detail view of the inside of the cabinet C looking out through the opening in the wall W which is to receive the projected end of the cathode ray tube;

Fig. 4 is a vertical sectional view taken through the shielding device of the present invention and the wall W on which it may be mounted;

Fig. 5 is an elevation of a piece of stock material from which the shielding device is to be constructed and erected;

Fig. 6 is a detail view showing one way in which the side walls of the shielding device may be fastened together;

Fig. 7 is a detail sectional view showing one way in which the lip 20L may be held down;

Fig. 8 is a partial perspective view of a corner of the shielding device embodying a modified kind of retaining lip or barb; and

Fig. 9 is a detail sectional view showing the manner of attaching such modified lip to the shield.

The present invention, as illustrated in Figs. 1 to 9, inclusive, embodies a housing or shielding device 20 adapted to fit over and around the free end of a cathode ray tube T that projects through the rear Wall W of a cabinet C housing the tube as in an ordinary television receiving set. The end of the tube T disposed outwardly of the rear wall W extends through an opening 21 in this Wall W, Fig. 4. In accordance with the present invention, the housing or cover 20 disposed about the projected tube end embodies projections that are passed through slots 22 formed in the wall W about the opening 21 and these projections include lips adapted to resist detachment of the housing 20 from the Wall W.

The shield or housing as 20 may be readily fabricated from a single piece of cardboard stock material or like stock material which is inherently strong and of a light and flexible nature. This shield is of a frusto-conical or frusto-pyramidal shape, closed at the rear end corresponding to the end of the tube T, and open at the other or base end which is to be mounted on the wall W of the cabinet C. In achieving this construction, resort may be conveniently had to a piece of blank stock material as 20B, Fig. 5, of predetermined size from which the developed outline of the housing 20 may be out, as for instance, in a single stamping operation. Thus, the blank 20B is provided at the central portion thereof with fold lines 20WF arranged as a square defining the rear wall 20RW of the shield 20. Integral with the wall ZtlRW and attached thereto along the fold lines 20 are four flaps which constitute the four side walls 208W of the frustocone-shaped housing 20. In the blank 20B, these four side wall members are separated from one another by relatively large V-shaped notches 20N stamped out from the blank 20B so as to account for the conical shape of the shield 20 which is to be erected from the blank 203. When the flaps constituting the four side walls 298W are folded inwardly toward each other about the fold lines 20WP, adjacent side edges of these walls engage each other and are joined as by angled metallic edge fasteners 30 of a known kind which include a plurality of interconnected hollow rivets 30L. These folding and fastening operations complete the major assembly of the housing 20, and it will be recognized that alternatives such as adhesive strips, or heat sealing if thermo-plastic material is used for the blank 20B, or other expedients may be resorted to instead of edge fasteners 30 for uniting the side walls 208W.

The shield or housing 20 that is thus erected from the developed blank 20B is to be secured to the Wall W of the cabinet C about the projected end of the cathode ray tube T by means formed along the peripheral edge at the base end of the housing, such means being extended through the slots 22 afforded about the opening 21 in the wall W. I achieve this in the present instance by providing the side Walls 208W of the housing with projections or with flanges 20F which project from the free edges thereof opposite the rear wall 20RW as shown in Fig. 5. Consonant with the one-piece feature of the shield 20, these flanges may be conveniently formed by stamping angled cut-outs from the two opposite outer corners of the four flaps in the blank 20B constituting the side walls of the housing 20 so as to form flat shoulders 208 in the walls 208W at either side of the flanges 20F.

Itis desirable that a housing 20 of this kind for the projected end of a cathode ray tube be mounted against inadvertent or purposeful withdrawal outwardly relative to the slots 22 in which the flanges 20F are mounted. To enable this to be accomplished in accordance with the present invention, lips are formed at the outer ends of the flanges 20F affording a barb attachment of the housing 20 to the inside of the cabinet C. One Way in which this may be accomplished is to provide additional fold lines 20LF, in the portions of the blank 20B that are to afford the flanges 20F, in spaced relation parallel to the outer free edges of the flanges 20F, and the strip portions of the blank 20B lying between the fold lines 20LF and such outer free edges of the flanges 20F afford lips 20L which may be folded back upon the fold lines 20LF provided therefor. When thus folded back, the lips 20L lie in planes spaced from the planes of the corresponding flanges 20F and may be fastened down at either end to I the flanges 20F as by staples 35, adhesive or in any other convenient manner.

The slots 22 in the wall W of the cabinet C for receiving the four flanges 20F and the attached retaining lips 20L are so arranged about the opening 22 in the Wall W through which the end of the tube T is projected as to enable the flanges 20F and the attached lips 20L to pass therethrough. Thus, a pair of opposite flanges 20F corresponding to a pair of opposite ones of the slots 22 are spaced apart from one another at their outer edges a distance somewhat greater than the lateral distance between such opposite ones of the slots 22 in the wall W that are to be associated therewith. and bv pressing in sli htly on the sides 208W of the shield 20, the flanges 20F may be slightly collapsed so as to be passable with the attached lips 20L through the slots 22 in the wall W to the extent permitted by the shoulders 20S engaging the face of the wall W. When the force collapsing the flanges 20F is relieved after mounting the shield in the slots 22. the flanges 20F will expand and press sli htly outwardly against the side edges of the slots to hold the shield in position on the wall W, and the retaining lips 20L are disposed just outwardly of the edges of the slots 22 at the inside of the wall W. When thus properly positioned, the lips 20L are effective to engage the inside of the wall W in the manner of a hook or abutment preventing inadvertent withdrawal of the shield 20 from the slots 22 as shown in Fig. 4. This disposes the rear wall 20RW of the shield 20 substantially from the end of the tube T so as to insure the tube T against damage.

It will be ap reciated that the lips as 20L are but one form of a lip aflording a hook or abutment on the flanges 20F for resisting or preventing withdrawal of the shield 20 away from the wall W, as strips of another kind carried at the free edges of the flanges 20F may be easily resorted to for engaging the inside of the cabinet C in a like manner. In Figs. 8 and 9, I illustrate the preferred form of such a lip afforded by fasteners like those used to secure together the side walls 208W. Thus, one leg 30B of a metal edge fastener 30A may be fastened by the rivets 30L provided thereon to the underside of each of the flanges 20F at the free ends thereof, and the other leg 30C of the fastener 30A is disposed as a lip projecting slightly above the plane of each flange 20F. The rivets 31 at either end of the leg 30C of each metal strip 30A are fastened to the flange 20F, and this assures that leg 30C will remain as a relatively rigid lip. Such lips 30C will serve as retaining abutments or hooks like the lips 20L engaging the inside of the cabinet C when the flanges 20F carrying the lips 30C are unflexed in the slots 22 to dispose the lips outwardly of the edges of the slots 22.

In the event'that it becomes necessary to dismount the shield 20, it is only necessary to press in slightly on the side walls 20SW thereof to disengage the lips as 20L or 30C from the inside face of the wall W, and when the lips are disposed in the area of the slots 22, the flanges 30C may be withdrawn therefrom. In this connection, it is important to note that the amount the lips as 20L and 30C protrude above the planes of the flanges on which they are carried is selected to achieve an optimum balance between firm attachment of the shield 20 to the cabinet C on one hand and ready mounting and dismounting of the shield 20 on the other.

From the foregoing it will be seen that in accordance with the present invention a housing or shield for the projected end of a cathode ray tube is afforded of such nature as to be readily fashioned from inexpensive stock material and mounted with facility on the cabinet housing the cathode ray tube. Being of general conical shape, the shield may be readily handled and transported, and the flanges about the periphery at the base of the housing are thereby adapted to engage openings provided therefor in the rear wall of the cabinet. In this manner, the housing may be easily mounted on the rear wall of the cabinet, and by providing retaining lips, preferably in the form of metal strips, on the outer ends of the flanges a barb attachment of the housing to the cabinet is afforded.

Hence, while I have illustrated and described the preferred embodiments of my invention, it is to be understood that these are capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. A shield for protecting the rear end portion of a cathode ray tube projected beyond one wall of a cabinet for housing the tube, said shield comprising a hollow housing open at the front end and formed from sheet material and affording a polygonal rear wall and side Walls corresponding in number to the edges of the rear wall and which are respectively joined to said rear wall along such edges, said side Walls abutting one another along adjacent side edges, means fastening the edge of each side wall to the abutting edge of the next adjacent side wall, and retaining means projecting beyond the forward edge portion of at least a plurality of the forward edge portions of the side Walls and including lips projecting outwardly of the edges of such side walls and which when passed through slots in the cabinet wall are urged yieldingly laterally of such slots to interlock with such wall and prevent inadvertent removal of the shield from the cabinet, said retaining means terminating short of the side edges of the respective side walls on which such means are provided to afford shoulders for engaging such a cabinet wall.

2. A shield for protecting the rear end portion of a cathode ray tube projected beyond the back wall of a cabinet for housing the tube, said shield comprising a hollow housing open at the front end and formed from sheet material affording a rectangular rear wall and four trapezoidal side walls integral with said rear wall along fold lines about which the side walls are folded forwardly to diverge forwardly and outwardly from said rear wall and abut one another along adjacent side edges, individual metal fastener strips including a plurality of rivets joining the adjacent edges of the side walls one to the other, flangescoplanar with and projecting forwardly of the forward edges of said side walls, said flanges terminating short of the side edges of said side walls to thereby form shoulders, said flanges being passable through corresponding slots afforded therefor in the back Wall of such a cabinet to engage said shoulders with said back wall and mount said shield thereon, and metal members secured on the forward edges of said flanges and affording metal li s projecting outwardly from said flanges and which when passed through said slots in such a wall of the cabinet will interlock with such back wall and prevent inadvertent removal of the shield from the cabinet.

3. A shield for protecting the end portion of a cathode ray tube projected beyond the back wall of a cabinet for housing the tube. said shield comprising a hollow housing open at the front end and formed from sheet mate-' rial affording a flat polygonal rear wall and relative side walls formed integral with the rear wall so as to extend forwardly in diverging relation from said rear wall and abut one another along adjacent side edges, fastener strips having angled legs joined one to the other each with fastening elements fastening the edge of each side wall to the abutting edge of the next adjacent side wall, integral flanges projecting forwardly of the forward edges of said side walls and in the planes of said side walls, said flanges terminating short of the side edges of said side walls to thereby form shoulders, said flanges being adapted to be passed through corresponding slots in the back wall of such a cabinet to engage said shoulders with said back wall and mount said shield thereon, a relatively rigid retaining lip at the forward edge portion of at least a plurality of said flanges projecting outwardly of the planes of the flanges so that when passed through such slots in the back wall of such a cabinet such lips interlock with the back wall and prevent inadvertent removal of the shield from the cabinet.

4. A shield for protecting the end portion of a cathode ray tube projected beyond the back wall of a cabinet for housing the tube, said shield comprising a hollow housing open at the front end and formed from sheet material affording a flat polygonal rear wall and relative side walls formed integral with the rear wall so as to extend forwardly in diverging relation from said rear wall and abut one another along adjacent side edges, fastener strips having angled legs joined one to the other each with fastening elements fastening the edge of each side wall to the abutting edge of the next adjacent side Wall, flanges projecting forwardly of the forward edges of said side walls and in the planes of said side walls, said flanges terminating short of the side edges of said side walls to thereby form shoulders, said flanges being adapted to be passed through corresponding slots in the back wall of such a cabinet to engage said shoulders with said back wall and mount said shield thereon, a relatively rigid retaining member secured in fixed position at the forward edge portion of at least a plurality of said flanges, said retaining member being made from metal and affording a retaining lip projecting above the planes of the flanges so that when passed through such slots in the back wall of such a cabinet prevent such lips interlocking with the back Wall and prevent inadvertent removal of the shield from the cabinet.

5. A shield for protecting the rear end portion of a cathode ray tube beyond the back wall of a cabinet for housing the tube, said shield comprising a hollow housing open at the front end and formed from relatively flexible sheet material affording a rear wall and side walls formed integrally with said rear wall along fold lines so as to close upon themselves and abut one another along adjacent side edges, fastener strips having a pair of legs joining the abutting edge portions of a pair of the side walls one to" the other, and means affording lips attached to forward edge portions of said side walls but terminating short of the side edges of the respective side walls to afford shoulders to engage the back wall of a cabinet, said lips being formed so as to project outwardly of the outer faces of the side walls and which when passed through slots in the back wall of such a cabinet interlock with the back wall and prevent inadvertent removal of the shield from the cabinet.

6. A shield for protecting the rear end portion of a cathode ray tube projected beyond one wall of a cabinet for housing the tube, said shield comprising a hollow housing open at the front end formed from sheet material affording a fiat polygonal rear wall and side walls integral therewith corresponding in number to the edges of the rear wall, said side walls abutting one another along adjacent side edges, means fastening the edge of each side wall to the abutting edge of the next adjacent side wall, and retaining means projecting beyond the forward edge portions of said side walls including lips projecting outwardly of the planes of the side walls and which when passed through slots in the cabinet wall are urged yieldingly laterally of such slots to interlock with such cabinet wall and prevent inadvertent removal of the shield from the cabinet, said retaining means terminating short of the side edges of the respective side walls to afford shoulders for engaging such a cabinet wall.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,956,196 Korab Apr. 24, 1934 2,236,557 Zalkind Apr. 1, 1941 2,642,566 Regnier June 16, 1953 

